Adenocard I.V.

WARNINGS

Heart Block

Adenocard (adenosine injection) exerts its effect by decreasing conduction through the A-V node and may produce a short lasting first-, second- or third-degree heart block. Appropriate therapy should be instituted as needed. Patients who develop high-level block on one dose of Adenocard should not be given additional doses. Because of the very short half-life of adenosine, these effects are generally self-limiting. Appropriate resuscitative measures should be available.

Transient or prolonged episodes of asystole have been reported with fatal outcomes in some cases. Rarely, ventricular fibrillation has been reported following Adenocard administration, including both resuscitated and fatal events. In most instances, these cases were associated with the concomitant use of digoxin and, less frequently with digoxin and verapamil. Although no causal relationship or drug-drug interaction has been established, Adenocard should be used with caution in patients receiving digoxin or digoxin and verapamil in combination.

Arrhythmias at Time of Conversion

At the time of conversion to normal sinus rhythm, a variety of new rhythms may appear on the electrocardiogram. They generally last only a few seconds without intervention, and may take the form of premature ventricular contractions, atrial premature contractions, atrial fibrillation, sinus bradycardia, sinus tachycardia, skipped beats, and varying degrees of A-V nodal block. Such findings were seen in 55% of patients.

Adenosine administered by inhalation has been reported to cause bronchoconstriction in asthmatic patients, presumably due to mast cell degranulation and histamine release. These effects have not been observed in normal subjects. Adenocard has been administered to a limited number of patients with asthma and mild to moderate exacerbation of their symptoms has been reported. Respiratory compromise has occurred during adenosine infusion in patients with obstructive pulmonary disease. Adenocard should be used with caution in patients with obstructive lung disease not associated with bronchoconstriction (e.g., emphysema, bronchitis, etc.) and should be avoided in patients with bronchoconstriction or bronchospasm (e.g., asthma). Adenocard should be discontinued in any patient who develops severe respiratory difficulties.

PRECAUTIONS

Carcinogenesis, Mutagenesis, Impairment of Fertility

Studies in animals have not been performed to evaluate the carcinogenic potential of Adenocard (adenosine injection). Adenosine was negative for genotoxic potential in the Salmonella (Ames Test) and Mammalian Microsome Assay.

Adenosine, however, like other nucleosides at millimolar concentrations present for several doubling times of cells in culture, is known to produce a variety of chromosomal alterations. Fertility studies in animals have not been conducted with adenosine.

Pregnancy Category C

Animal reproduction studies have not been conducted with adenosine; nor have studies been performed in pregnant women. As adenosine is a naturally occurring material, widely dispersed throughout the body, no fetal effects would be anticipated. However, since it is not known whether Adenocard can cause fetal harm when administered to pregnant women, Adenocard should be used during pregnancy only if clearly needed.

Pediatric Use

No controlled studies have been conducted in pediatric patients to establish
the safety and efficacy of Adenocard for the conversion of paroxysmal supraventricular
tachycardia (PSVT). However, intravenous adenosine has been used for the treatment
of PSVT in neonates, infants, children and adolescents (see DOSAGE AND ADMINISTRATION).

Geriatric Use

Clinical studies of Adenocard did not include sufficient numbers of subjects
aged 65 and over to determine whether they respond differently from younger
subjects. Other reported clinical experience has not identified differences
in responses between elderly and younger patients. In general, Adenocard in
geriatric patients should be used with caution since this population may have
a diminished cardiac function, nodal dysfunction, concomitant diseases or drug
therapy that may alter hemodynamic function and produce severe bradycardia or
AV block.

Last reviewed on RxList: 12/3/2009
This monograph has been modified to include the generic and brand name in many instances.